"Couldn't find the Firefox executable" when launching in attach mode

[FieteO]

I am getting the Couldn't find the Firefox executable when launching in attach mode. I am asking myself now if this is a wanted behaviour, since I wouldn't expect that the executable is needed for that.

Background

I was following the instructions for launching in attach mode in the README. Accordingly, I have set up a launch.json that contained the recommended block:

{
    "version": "0.2.0",
    "configurations": [
        {
            "name": "Attach to localhost",
            "type": "firefox",
            "request": "attach",
            "url": "http://127.0.0.1/"
        }
    ]
}

My firefox had the necessary about:config changes and launched fine in debug mode with

"C:\Program Files\Mozilla Firefox\firefox.exe" -start-debugger-server

When I launched the debug session in vscode with this configuration I got the Couldn't find the Firefox executable error.

Cause

The firefox.executable config was set globally to a wrong location.

Two things that I think would have improved my situation

• the error message would point out that this is set in the global extension settings
• the error would not be thrown since (correct me if I am wrong) the executable is not called at all in attach mode

[Miguel-Dias-112]

just put "firefoxExecutable": (path to .exe ) in your json file